Arduino compatible high precision frequency meter

I would like to expose you a project that I started already 4 months ago and it is running at low speed. It is much more complicated than I expected. I had to change the design, find a manufacturer and source components etc. So now I am prototyping the board and I guess I will have to prototype a couple of version to reach the goal. I built a WP page to present the project there : http://pandauino.com/wp/en/home/